minimum viable rails

fake_rails.rb

unless defined?(Rails)
  # minimum viable implementation of Rails
  class Rails
    class << self
      def root
        Pathname.new(File.expand_path('../..', __FILE__))
      end

      def env
        'test'.tap do |e|
          def e.test?
            true
          end
        end
      end

      def test?
        true
      end
    end
  end
end